The Effect of Hyaluronidase on the Fat Graft

High-Level Extracellular Expression of Hyaluronate Lyase HylP in Bacillus subtilis for Hyaluronan Degradation

Hyaluronate lyase (HA lyase) has potential in the industrial processing of hyaluronan. In this study, HylP, an HA lyase from Streptococcus pyogenes phage (SPB) was successfully expressed in Bacillus subtilis. To improve the extracellular enzyme activity of HylP in B. subtilis, signal peptide engineering systematic optimization was carried out, and cultured it from shake flasks and fermenters, followed by purification, characterization, and analysis of degradation products. The results showed that the replacement of the signal peptide increased the extracellular enzyme activity of HylP from 1.0 × 104 U/mL to 1.86 × 104 U/mL in the shake flask assay, and using a 20 L fermenter in a batch fermentation process, the extracellular enzyme activity achieved the level of 1.07 × 105 U/mL. HylP exhibited significant thermal and pH stability in the temperature range of 40 °C and pH range of 4-8, respectively. The enzyme showed optimum activity at 40 °C and pH 6, with significant activity in the presence of Na+, Mg2+, and Co2+ ions. Degradation analysis showed that HylP efficiently degraded hyaluronan as an endonuclease, releasing unsaturated disaccharides. These comprehensive findings underscore the substantial industrial potential of HylP for hyaluronan processing applications, offering valuable insights into enzyme characterization and optimization of expression for potential industrial utilization.

The Utility of Hyaluronidase for the Free and Pedicle Flap Salvage

Hyaluronidase is commonly used to treat swelling and hematoma for aesthetic and reconstructive purposes. It has also been reported as a stimulator of angiogenesis. The purpose of this study was to introduce the utility of hyaluronidase in patients with flap compromise after free and pedicle flap reconstructions. This study was a retrospective study of 1 case of radial forearm free flap salvage, 2 cases of keystone perforator flap salvage, and 1 case of pectoralis major myocutaneous flap salvage. A radial forearm free flap reconstruction of unilateral mouth floor and tongue defect was complicated with hematoma formation on a postoperative day 1 after taking clopidogrel due to acute-onset non-ST-elevation myocardial infarction but dramatically resolved with hyaluronidase injection into the flap and contralateral unaffected tongue. After this intervention, the flap color dramatically returned to normal and became soft without further treatments. Two keystone design perforator flaps were performed to reconstruct the sacral defect after the debridement of pressure ulcers. Two cases were related to the patients' medical conditions, such as low platelet count caused by liver cirrhosis. We also salvaged pectoralis major myocutaneous flap in a 91-year-old female patient with large breasts. This study introduced our experience of salvaging the free and pedicled flaps using hyaluronidase. Hyaluronidase is an excellent option when arterial or venous insufficiency occurs after free and perforator flap surgeries.

Study of platelet-rich plasma application for skin and plastic surgery in recent 20 years: A bibliometric analysis

BACKGROUND

In recent years, platelet-rich plasma (PRP) has been used in plastic surgery, dermatology, and other treatment procedures worldwide. Since the number of scientific writings has been significantly increasing, it is challenging to generate a manual compilation and systematic review of PRP's therapeutic applications in dermatology and plastic surgeries. This study aimed to make a bibliometric analysis of the literature in the field and evaluate research hotspots and frontiers in this field in the past 20 years.

METHODS

Using the Academic Search Premier and ScienceDirect defined search terms, we searched the Web of Science Core Collection (WoSCC) and Scopus databases. All data were analyzed using CiteSpace 5.8.R3 and VOSviewer, including countries, institutions, authors, keywords, cited authors, cited journals, cited references, discovered research hotspots, and frontiers.

RESULTS

A total of 1931 studies were retrieved. The number of publications on PRP application in dermatology and plastic surgeries showed a yearly increase. The United States was the most significant contributor to this field, while Italy's contribution was noteworthy. The journal with the highest number of relevant articles in dermatology and plastic surgery included the Journal of Cosmetic Dermatology. However, the Wound Repair and Regeneration and International Journal of Molecular Sciences were the leading journals that should be paid attention to in the future. Author Anitua E from the Tor Vergata University of Rome published the most publications in this field. In the keyword co-occurrence analysis, all keywords were divided into six clusters, and the most common one in recent years was "PRP for facial beauty." Facial rejuvenation, scar, and alopecia were the main hotspots and research trends in this field.

CONCLUSIONS

Based on the current global trends, the use of PRP in cosmetics and skin care is receiving increasing attention from researchers and clinicians. Recently, an increasing number of articles on PRP's application in skin tissue repair have been published in the United States and Italy. The number of studies on hair loss, facial rejuvenation, and scar management is increasing, suggesting that these subjects may become research hotspots for PRP in dermatology and cosmetic surgeries in recent years.

Insights into the source, mechanism and biotechnological applications of hyaluronidases

It has long been found that hyaluronidases exist in a variety of organisms, playing their roles in various biological processes including infection, envenomation and metabolic regulation through degrading hyaluronan. However, exploiting them as a bioresource for specific applications had not been extensively studied until the latest decades. In recent years, new application scenarios have been developed, which extended the field of application, and emphasized the research value of hyaluronidase. This critical review comprehensively summarizes existing studies on hyaluronidase from different source, particularly in their structures, action patterns, and biological functions in human and mammals. Furthermore, we give in-depth insight into the resource mining and protein engineering process of hyaluronidase, as well as strategies for their high-level production, indicating that mixed strategies should be adopted to obtain well-performing hyaluronidase with efficiency. In addition, advances in application of hyaluronidase were summarized and discussed. Finally, prospects for future researches are proposed, highlighting the importance of further investigation into the characteristics of hyaluronidases, and the necessity of investigating their products for the development of their application value.

The Effect of Locally Delivered Apocynin on Fat Graft Survival in an Experimental Rat Animal Model

OBJECTIVES

We aimed to investigate the efficacy of locally delivered apocynin on fat graft survival in an experimental autologous fat grafting (AFG) model created in rats.

METHODS

Twenty-one Wistar albino male rats were included in this study. The 0.647 g mean weight grafts were harvested from the inguinal region and transferred to the nape of every rat. The subjects were randomly separated into three groups. Saline, dimethyl sulfoxide (DMSO) and apocynin, a dose of 20 mg/kg, solutions were applied once a day for 2 weeks. After 3 months, the rats were sacrificed. The evaluation of physical measurements (weight and volume) and survival rates of the grafts for volume (SRV) and weight (SRW), the viable cell count (VC) with the MTT assay, and histopathological parameters were done.

RESULTS

All biophysical parameters were found to be significantly higher in the apocynin group compared to other groups (p < .05). In the MTT test, the saline group was normalized to 100%. According to this, DMSO and apocynin groups' means were 106% and 163%, respectively. The VC was significantly higher in the apocynin group than the other groups (p < .05). The VC was significantly higher in the DMSO group than in the saline group (p < .05). No significant difference was found in other comparisons performed according to biophysical and histopathological parameters (p > .05).

CONCLUSION

The locally delivered apocynin decreases fat graft volume loss in an experimental AFG model. Consequently, apocynin can be used as an effective substance to increase graft survival.

Use of hyaluronidase in plastic surgery: A review

Hyaluronidase is a family of enzymes that degrade hyaluronic acid (HA). It is found to increase vascular permeability and temporarily disrupt the extracellular matrix, promoting diffusion of substances through tissues. Alongside its applications in ophthalmology, obstetrics and gynaecology, musculoskeletal medicine, radiology and drug and fluid administration, hyaluronidase has a number of roles in the field of plastic surgery. The popularity of HA fillers in recent years has led to an increase in the usage of hyaluronidase in the treatment of filler-related complications. The purpose of this article is to review the current and future uses of hyaluronidase within the field of plastic surgery. Hyaluronidase is used as an adjunct to local anaesthetics in skin infiltration, skin graft harvesting, tumescent analgesia, managing complications of dermal fillers, treatment of extravasation injury, prevention and management of oedema, treatment of ganglion and management of scars. However, it has some limitations. Hyaluronidase is known to interact with a number of common medications. Several case reports also highlight the risk of allergic reaction to the substance. Although rare and usually mild, hyaluronidase has the potential to cause anaphylaxis. Other adverse effects include bruising and swelling. Overall, hyaluronidase appears to be a very safe, cheap and effective medication for a variety of uses in the field of plastic surgery and beyond.